Car-door lock.



R. T. ROBERTS.,

CAR DOOR LOCK. APPLICATION FILED MAY 23. |918 Ameme@ 1mb., 18, 1919,

2 SHEETS-SHEET l.

R. T. ROBERTS.

CAR noon Loma,

APPLICATION FILED MAY 23. \913.

Patented Feb., M8, W19..

WITNESSES ROCKWOOJD T. ROBERTS, OF WORCESTER, MASSACHUSETTS.

cnnfnoon. Locri.

Specification of Letters Patent.

Patented Feb.. 13, 1919.

Application led May 23, 1918. Serial No. 236,206.

To all 'whom t may concern.'

Be it known that I, Rockwool) T. ROBERTS, a citizen of the United States, residing at Worcester, in the county of Worcester and State of Massachusetts, have invented a. new and Improved Car-Door Lock, of which the following is a full, clear, and eXact description.

My invention relates to cai' door locks which are adapted to. be mounted within the body of thedoor s o that the locking mechanism cannot be broken to get access into the car.

An object of the invention is to provide a simple, strong and inexpensive lock for which a specially-constructed key is required to operate the locking mechanism.

With the above and other objects in view, the nature of which will more fully appear as the description proceeds, the invention consists in the novel construction, combina.- tion and arrangement of parts as herein fully described, illustrated and claimed.

In thel accompanying drawings, forming part of the application, similar characters of reference indicate corresponding parts in all the views.

Figure 1 is an elevation of a car door provided with a lock embodying my invention,

a certain part of the car structure being broken away to show the details of construction;

Fig. 2 is a vertical cross section through a car door equipped with a lock embodying my invention;

Fig. '3 is an enlarged front elevation of the locking mechanism proper;

Fig. 4 is a vertical section on line 4 4,

Fig'. 3;

Fig. 5 is a horizontal cross section on lme the locking mechanism.

vReferring to the drawings, 8 is a lock casing, which is in the shape of a cylindrical cup having a centralv depression 9 in the bottom which serves as a bearing for a trunnion 10 of a tuublerl 11 which fills the casing 8. The tumbler has a reduced cylindrlcal portion 12 which projects out of the casing 8 to engage a flange 13 which forms the cover for the casing and locks the tumbler in the casing. 'Ihe cover and casing have registering openings for receiving bolts 14 by means 'of which thelock is secured to the door 15 of a car.

The tumbler 11 has an elbow-shaped opening 16 `(see Fig. 4) leading to a rectangular recess 17. which opens into the periphery of the tumbler' and with which a similar recess 18 of the ,housing may register when the tumbler is turned. The rectangular recesses I7 and 18 are adapted to receive a plunger 19 subject to pressure of a spring 20 locked in the recess 18. When the recesses 17 and 18 are in register the spring 20 will force the plunger 19 from the recess 18 into the recess 17 and bind the tumbler to the casing 8 thereby preventing the rotation of the tum bler within the casing.

' The plunger 19 is displaceable by the elbow;shaped pin 2l of the key 22 which can be engaged in the elbowshaped opening 16 of the tumbler, thereby bringing the pin 2l against the plunger 19. The movement of the pin 21 into the elbow-shaped opening 16 forces the plunger 19 out of the recess 17 until the bottom of the plunger is above the rounded edge 23 of the recess 17. The key 22 has also a. straight pin 24 for which the tumber has a recess 25. This pin 24 enters the recess 2-5 when the plunger is displaced as described. By applying pressure to the-key the tumbler can now be turned to the right, for the rounded edge 23 in its turning will move the plunger into the recess 18 against the resistance of the spring 20.

'Ihe tumbler 1l also carries bolts 26 which are pivotally connected thereto and for which the casing 8 has slots 27 to provide the necessary clearance required for the dise placement of the bolts when the tumbler is turned in the manner as described .and whereby said bolts are drawn out of the sockets 28 providedin the door frame.

In Fig. 7 a bolt 29 is rigidly connected to the tumbler. The bolt has an extension 30 in the plane of its motion adapted to enter the recess 31 o1" the bolt socket in the door frame and whereby the door is locked to the frame when the extension 30 is in the recess 31. By turning the tumbler in the manner as described the extension 3() may swing out from the recess .and thereby the door unlocked as can be easily seen.

I claim:

1. In a lock of the class described, a casing, a tumbler revolubly mounted in the casing and having an angular recess, a plunger mounted in the casing and adapted to engage the recess of the tumbler to prevent the same from turning, a door bolt operable by the turning of the tumbler, and a key having an angular pin and a straight pin,

the angular pin engaging the plunger to move it partly out of the recess of the tumbler and lthe straight pin engaging the tumbler to turn the same to cause it to force the plunger entirely out of said recess and to operate the bolt.

2. In a lock of the class described, a cylindrical casing, a tumbler revolubly mounted in said casing, a cover for said casing adapted to lock the tumbler in the casing, a spring-actuated polygonal plunger located in said casing and adapted to engage the tumbler and whereby the same is prevented from turning, a key having an elbow-shaped pin for engaging and displacing the plunger from the tumbler into the casing and a straight pin for engaging the tumbler to turn Ithe samey after the plunger has been operated by the elbow-shaped pin, and a. door bolt operable by the turning movement of the tumbler.

In a lock of the class described, a cylindrical casing open at one end, a tumbler revolubly mounted in said casing, a cover for said casing having means for engaging the tumbler so as to present a portion of same at the face of the cover,l a spring-actuated plunger of rectangular cross section located in the casing, said tumbler having a recess in the lateral surface to one side into which the plunger is adapted to enter when said recess registers With/the plunger, the engagegage the plunger and force the same into the casing so that th'e bottom of the plunger comes above one of the edges of the recess, and said straight pin engaging the tumbler to turn the same and cause it to force the plunger into the casing against the resistance of the spring, and a door bolt operable by the turning movement vof the tumbler.

ROCKWOOD T. ROBERTS. 

